Improvement in feeding mechanisms for rock-drills



I. DUTY.

Feeding-Mechanisms for Rock-Drills. Nb, 140,767, PatentedJuly15,187 3.

AM, Pflora-umaammwc 00 N Moseamvs's FHQCESS) UNITED STATES PATENT OErIcE.

JOHN DOTY, 0E BUFFALO, NEW 'YORK.

IMPROVEMENT IN FEEDING MECHANISMS FOR ROCK-DRILLS.

Specification forming part of Letters Patent No. 140,767, dated July 15-, 1873; application filed May 3, 1873.

To all whom it may concern:

Be it known that I, JOHN DOTY, of Bufialo, in the county of Erie and.State of New York, have invented certain new and useful Improvements in Rock-Drills, of which the following is a specification:

This invention relates to an improvement in the manner of working the feed-lever which operates the bit of the drill, andthe feed-catch or qualifier employed in what are known as the Burleigh rock-drill. The invention consists in the combination, with the feed-box, of a coiled spring and a qualifier having a pin, to which said spring is attached, the other end working or hearing in a slot in the feedbox. It further consists in a novel and peculiar-formed qualifier, which is fully hereinafter explained; and it further consists of certain other improvements, all of which are herein after it has been thrown up'by the projection D, I arrange a coiled spring, I), as shown, one end resting on the back of the lever and the other against the feed-box cover. To hold it in place I make a kind of box by setting at right angles with and in the sides of the feedbox A two partitions, c c. This prevents the spring from falling out of position, but can be taken out by removing cover a of the 'feedbox. The lower ends of the partitions c 0 do not come down to the lever-arm, but allow of a free movement of it, one partition, 0, being shorter than the other for that purpose. As fast as the lever is thrown up by the pistonhead it is returned to its normal position by the spring.

This spring might be held by a pin attached to the lever, and another inserted through the cover of the feed-box and through the center of the spring; but the way shown is preferable, being simpler.

I am aware that usually the change of one kind of spring for another is not considered invention; but in this case the change and arrangement of springs is of so much importance in working and value to the machine that it is now considered well nigh indispensable.

The same kind of spiral spring, 6, is used also in the feed-box in connection with the qualifier O, the latter working on a pivot, 01. The spring 0 is held in place by its lower end inclosin g a pin, f, attached to the lower or pointed end of the qualifier, the other end of the spring resting in a slot, g, made in the end of the feed-box, the cover a aiding to hold the spring in place, and also allowing its being easily taken out.

The improved form of the qualifier or feedcatch 0 is of very great importance also; and the objections to the others I overcome by makin g a more gradual rounding of the lower part, and the relative position of the end with the other parts making a new feed-catch of it.

I claim- 1. The combination of the coiled spring 6, qualifier 0, pin f, and slot g, arranged and operating substantially as described.

2. The qualifier C with its pin f, constructed substantially as described, for the purpose specified.

3. The lever B and qualifier O, in combina- Witnesses J. R. DRAKE, GEo. H. DUNBAR. 

